Sizing the GBX 160 for servo pairing
The Schneider Electric GBX1600031084D is a planetary gearbox in the GBX series, sized to a 160 mm frame with a straight-tooth gear set and a 3:1 reduction — the headline number a sizing engineer runs first because it sets both the output speed and the torque the downstream coupling sees. Continuous output torque is rated at 400 N.m and the peak sits at 640 N.m; against a 96 % efficiency figure, the gearbox itself burns roughly 4 % of the input power as heat, so at full continuous load the thermal margin is dominated by the case-to-mounting-surface path rather than by internal gear friction. Service life is published at 30,000 h at 100 rpm and 30 °C — the published load ratings below are derated for that life; running hot or fast shortens the window on the same bearing and gear set.
Backlash, rigidity and the load the shaft can take
Maximum torsional backlash is 6 arc.min and torsional rigidity is 38 N.m/arcmin, so a positioning application sees roughly 0.16° of wind-up at the continuous torque rating — small enough for most servo point-to-point moves, but worth checking against the application's accuracy budget. The moment of inertia reflected back to the input is 12.14 g.cm², which keeps the gearbox from dominating the drive's acceleration loop in mid-size servo pairings; combined with 70 dB at 1 m no-load the unit is quiet enough for indoor cells without acoustic enclosure. Shaft loading is split into two regimes: up to 6000 N axial and 4200 N radial at 100 rpm for the published 30,000 h life, rising to 8000 N axial and 6000 N radial if the application is sized for only 10,000 h — the lower-force numbers are the ones to design against for long-duty installations like conveyors and palletisers.
Sealing, environment and where it physically bolts in
IP54 at the shaft output seals against splashing water and dust but not against high-pressure washdown, so the GBX1600031084D suits general factory floors and machine interiors rather than food-grade or outdoor cabinets; ambient operating range is -25 to 90 °C. The housing is black anodized aluminium with a C 45 steel output shaft, lubricated for life — no grease fittings to schedule in the maintenance plan, but a confirmed service interval on the application side rather than a mid-life regrease. Mounting position is unrestricted, so the gearbox can be oriented to suit the machine layout; the matching servo coupling and the GBX-series adapter kit are what line up to the drive, not the gearbox itself.